Peripheral hypersensitivity to subthreshold stimuli persists after resolution of acute experimental disc-herniation neuropathy

Objective: While acute disc-herniation radiculopathy frequently resolves without clinical sequelae, some patients experience long-term sensory or motor dysfunction. This study examined chronic sensitivity of the rodent hindpaw after resolution of an acute inflammatory neuropathy. Methods: C57BL/6 mice underwent mid-thigh sciatic nerve exposure, with sham animals exposed and experimental animals injured by placement of littermate tail nucleus pulposus (NP). Animals were evaluated for mechanical allodynia (Von Frey), thermal sensitivity (heat withdrawal and acetone latency), and gait stability (RotaRod), until the acute nociceptive phenotype resolved. Thereafter, animals were injected with intraplantar subthreshold capsaicin or vehicle followed by the same testing. At sacrifice, sciatic nerves were assessed for macrophage infiltration by immunohistochemistry, and dorsal root ganglion (DRG) explants were assessed for capsaicin sensitivity using cobalt staining. Results: NP-treated animals were allodynic after subthreshold capsaicin delivery compared with sham-operated controls and NP-treated animals delivered vehicle only. Early intraneural macrophage infiltration at one week dissipated by this three week timepoint. DRGs derived from NP-treated animals exhibited greater cobalt staining upon capsaicin exposure compared with shams. Conclusion: Non-compressive disc herniation creates long-term sensitization in the sciatic nerve distribution. This persists despite resolution of acute intraneural macrophage migration, and the demonstrated role of TRPV1 provides insight into the transformation of acute inflammatory pain into chronic neuropathic pain.

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Clearance of peripheral nerve misfolded mutant protein by infiltrated macrophages correlates with motor neuron disease progression

Scientific Reports ◽

10.1038/s41598-021-96064-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Wataru Shiraishi ◽

Ryo Yamasaki ◽

Yu Hashimoto ◽

Senri Ko ◽

Yuko Kobayakawa ◽

...

Keyword(s):

Sciatic Nerve ◽

Peripheral Nerves ◽

Disease Onset ◽

Green Fluorescence Protein ◽

Macrophage Infiltration ◽

Fluorescence Protein ◽

End Stage ◽

Als Patients

AbstractMacrophages expressing C–C chemokine receptor type 2 (CCR2) infiltrate the central and peripheral neural tissues of amyotrophic lateral sclerosis (ALS) patients. To identify the functional role of CCR2+ macrophages in the pathomechanisms of ALS, we used an ALS animal model, mutant Cu/Zn superoxide dismutase 1G93A (mSOD1)-transgenic (Tg) mice. To clarify the CCR2 function in the model, we generated SOD1G93A/CCR2Red fluorescence protein (RFP)/Wild type (WT)/CX3CR1Green fluorescence protein (GFP)/WT-Tg mice, which heterozygously express CCR2-RFP and CX3CR1-GFP, and SOD1G93A/CCR2RFP/RFP-Tg mice, which lack CCR2 protein expression and present with a CCR2-deficient phenotype. In mSOD1-Tg mice, mSOD1 accumulated in the sciatic nerve earlier than in the spinal cord. Furthermore, spinal cords of SOD1G93A/CCR2RFP/WT/CX3CR1GFP/WT mice showed peripheral macrophage infiltration that emerged at the end-stage, whereas in peripheral nerves, macrophage infiltration started from the pre-symptomatic stage. Before disease onset, CCR2+ macrophages harboring mSOD1 infiltrated sciatic nerves earlier than the lumbar cord. CCR2-deficient mSOD1-Tg mice showed an earlier onset and axonal derangement in the sciatic nerve than CCR2-positive mSOD1-Tg mice. CCR2-deficient mSOD1-Tg mice showed an increase in deposited mSOD1 in the sciatic nerve compared with CCR2-positive mice. These findings suggest that CCR2+ and CX3CR1+ macrophages exert neuroprotective functions in mSOD1 ALS via mSOD1 clearance from the peripheral nerves.

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Optimization of surgical outcomes with prehabilitation

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2015-0084 ◽

2015 ◽

Vol 40 (9) ◽

pp. 966-969 ◽

Cited By ~ 40

Author(s):

Daniel Santa Mina ◽

Celena Scheede-Bergdahl ◽

Chelsia Gillis ◽

Francesco Carli

Keyword(s):

Nutrition Education ◽

Hospital Length ◽

Hospital Length Of Stay ◽

Life Outcomes ◽

Readmission Rates ◽

Behaviour Changes ◽

Psychosocial Approaches ◽

Patients Experience

The concept of preparing surgical candidates with various modalities designed to increase physical, physiological, metabolic, and psychosocial reserves is known as prehabilitation. Prehabilitation has garnered significant attention in recent years as evidence grows describing benefits to clinical and quality of life outcomes. Recent research examining hospital length of stay and readmission rates provides promising findings with respect to the value of prehabilitation in economic and sustainable healthcare models. The role of prehabilitation across the surgical experience exploits common surgical wait-times and the teachable moment that many patients experience upon the identification of a surgical requirement to improve the pre-, peri-, and postoperative experience. Prehabilitation incorporates numerous systemic and regional approaches to conditioning the surgical candidate. These include exercise, nutrition, education, and/or psychosocial approaches that are intended to improve preoperative fitness and preparedness. Importantly, this also promotes and facilitates health behaviour changes not only preoperatively but during the postoperative period and over the long-term. In this paper, we briefly review the historical and current perspectives on prehabilitation and comment on opportunities for greater clinical and empirical understanding in this field.

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Role of Craniotomy Repair in Reducing Postoperative Headaches After a Retrosigmoid Approach

Neurosurgery ◽

10.1227/neu.0b013e3181f0bbf1 ◽

2010 ◽

Vol 67 (5) ◽

pp. 1286-1292 ◽

Cited By ~ 19

Author(s):

Mario K Teo ◽

M Sam Eljamel

Keyword(s):

Risk Factors ◽

Length Of Hospital Stay ◽

Outcome Data ◽

Similar Data ◽

Postoperative Headache ◽

Patients Experience ◽

Prospective Database

Abstract BACKGROUND: The retrosigmoid (RS) approach provides an excellent access corridor to the cerebellopontine angle. However, 80% of patients experience headaches after RS approaches. OBJECTIVE: We reviewed our prospective database to determine the risk factors influencing headaches after RS procedures. METHODS: From 2003, craniotomy, instead of craniectomy, became our standard approach for RS procedures. Patients' demographic, management, and outcome data were collected prospectively. We also retrospectively analyzed similar data collected between 2000 and 2003 to compare headache outcomes after RS approaches. Subgroup analysis of data was performed to identify other risk factors contributing to postoperative headaches. RESULTS: Of 105 patients (mean age, 56 years; 43 men; 62 women) who underwent RS surgery, 30 underwent craniectomy and 75 underwent craniotomy. There were 57 vestibular schwannomas, 40 microvascular decompressions, and 8 other procedures. The patients' age, sex, pathological diagnosis, and length of hospital stay were not statistically different in the 2 subgroups. At discharge, postoperative headache was observed in 43% of patients (13/30) after craniectomy and 19% of patients (14/75) after craniotomy (P = .01). The incidence of headache decreased with further follow-up; 10% of patients (3/30) who underwent craniectomy and 1% of patients (1/75) who underwent craniotomy still had headache at 12 months of follow-up. CONCLUSION: Patients who underwent the RS approach with craniotomy had a significantly lower rate of headache at discharge than did those who underwent craniectomy. These patients continued to have a lower incidence of headache in the long term.

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The Effect of Long Term Administration of Aspartame on the Sciatic nerve of adult male albino rats and the Possible Therapeutic Role of Ozone (Histological and Biochemical Study)

Egyptian Journal of Histology ◽

10.21608/ejh.2018.6082.1035 ◽

2019 ◽

Vol 42 (1) ◽

pp. 191-201 ◽

Cited By ~ 1

Author(s):

Ebtehal Hassen ◽

abeer mahmod ◽

Nahla Ibrahem ◽

Amal El-Shal

Keyword(s):

Sciatic Nerve ◽

Adult Male ◽

Biochemical Study ◽

Albino Rats ◽

Therapeutic Role ◽

Term Administration

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Impact of Catheter Ablation on Stroke, Cognitive Decline and Dementia

Arrhythmia & Electrophysiology Review ◽

10.15420/aer.2021.42 ◽

2021 ◽

Vol 10 (3) ◽

pp. 205-210

Author(s):

Tyson S Burnham ◽

Monte L Scott ◽

Benjamin A Steinberg ◽

Daniel L Varela ◽

Brian Zenger ◽

...

Keyword(s):

Catheter Ablation ◽

Cognitive Decline ◽

Antiarrhythmic Drugs ◽

Cognitive Testing ◽

Multiple Forms ◽

Free Survival ◽

Patients Experience

AF has been consistently associated with multiple forms of dementia, including idiopathic dementia. Outcomes after catheter ablation for AF are favourable and patients experience a better quality of life, arrhythmia-free survival, and lower rates of hospitalisation compared to patients treated with antiarrhythmic drugs. Catheter ablation is consistently associated with lower rates of stroke compared to AF management without ablation in large national and healthcare system databases. Multiple observational trials have shown that catheter ablation is also associated with a lower risk of cognitive decline, dementia and improved cognitive testing that can be explained through a variety of pathways. Long-term, adequately powered, randomised trials are required to define the role of catheter ablation in the management of AF as a means to lower the risk of cognitive decline, stroke and dementia.

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Renal injury in streptozotocin-diabetic Ren2-transgenic rats is mainly dependent on hypertension, not on diabetes

AJP Renal Physiology ◽

10.1152/ajprenal.00088.2006 ◽

2007 ◽

Vol 292 (2) ◽

pp. F820-F827 ◽

Cited By ~ 17

Author(s):

Andrea Hartner ◽

Nada Cordasic ◽

Bernd Klanke ◽

Michael Wittmann ◽

Roland Veelken ◽

...

Keyword(s):

Diabetic Nephropathy ◽

Macrophage Infiltration ◽

Sprague Dawley ◽

Term Study ◽

Hypertensive Nephrosclerosis ◽

Matrix Deposition ◽

Long Term Study

Induction of streptozotocin (STZ) diabetes in hypertensive rats transgenic for the mouse ren-2 gene (TGR) has been described as a model of progressive diabetic nephropathy. We investigated the long-term course of STZ diabetes in TGR and appropriate Sprague-Dawley control rats (SD) and tested the role of angiotensin-dependent hypertension by treating rats with the angiotensin II type 1 receptor blocker losartan (1 mg·kg−1·day−1) via osmotic minipumps. Five weeks after STZ injection, diabetes developed in TGR and SD. Urinary albumin excretion was increased by diabetes and, to a much higher degree, by hypertension. The effects of hypertension and diabetes were not additive, and only the effects of hypertension were ameliorated by losartan. A similar pattern was observed for cell proliferation and macrophage infiltration in the kidney. In contrast, the effects of hypertension and diabetes on glomerular collagen IV accumulation were additive 5 wk after STZ injection. In a long-term study for 20 wk after STZ, survival was better in STZ-treated TGR than in normoglycemic TGR, whereas all SD survived. Impaired creatinine clearance and increased macrophage infiltration as well as glomerular and interstitial matrix deposition were prominent in TGR compared with SD, regardless of the presence or absence of diabetes. In conclusion, STZ diabetes in TGR may be useful to study glomerular and interstitial matrix deposition early in the course of diabetes. However, the long-term course of this animal model resembles severe hypertensive nephrosclerosis, rather than progressive diabetic nephropathy.

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